Bertrand Delanoë, the mayor of Paris, must be wishing he had never opened his mouth to criticise the damage protesters against same-sex marriage did to one of the city's most exclusive central parks.

When opponents of the government's bill to allow "marriage for all" gathered on the Champ-de-Mars, in the shadow of the Eiffel tower, on 13 January, the normally pristine lawns were destroyed by the trampling of an estimated 350,000 of pairs of feet.

Delanoë supports the proposed legislation, which would fulfil an election pledge from the Socialist president, François Hollande. The mayor complained that the demonstrators had caused damage to around 3,600 sq metres of grass, which would cost at least €100,000 (over £80,000) to repair. The grass was supposed to have been "resting" over winter.

After the interior ministry, which authorised the gathering, refused to pay up, Delanoë said he would be sending the bill to the organisers of the protest .

"Those are the rules," he insisted, saying it was "normal and legitimate" to ask for damages. He added that he had presented bills to the rock star Johnny Hallyday, in 2009, and SOS Racisme, in 2011, after fans and supporters caused similar damage.

In response to his demand, anti-gay marriage organisers urged supporters to send cheques for between 10 centimes and €1 to the Paris city hall; about 9,000 people did so.

While the gesture has raised around €900 towards repairs, it has caused more trouble than it is worth.

Delanoë told France Bleu radio he did not know what to do with the money as he was obliged to issue a receipt for each and every donation. Apart from the cost of staff time and envelopes, he added, "it's going to cost me more in stamps than I've received".

Officials say the Champ-de-Mars lawns, which normally reopen in April, will remain closed off to the public until June.

The bill allowing same-sex couples to marry was passed in an Assemblée Nationale vote earlier this month, and will be voted on by the Sénat, the upper house, on 2 April.